What is the pollution of PCBA circuit board?

Pollutants are defined as any surface deposits, impurities, slag inclusions and adsorbates that reduce the chemical, physical or electrical properties of PCBA to unqualified levels.

The pollutants in PCBA manufacturing are mainly applied to the cleaning process in the following aspects:

① The components constituting PCBA, the pollution or oxidation of PCB itself will bring PCBA board surface pollution.

② In the production and manufacturing process of PCBA, solder paste, solder wire, etc. need to be used for welding. The flux in the welding process will produce residues and pollute the PCBA board surface, which is the main pollutant.

③ Hand marks will be produced in the process of manual welding, and some wave soldering pawl marks and welding tray (fixture) marks will be produced in the process of wave soldering. There may also be other types of pollutants on the surface of PCBA, such as hole plugging glue, residual glue of high-temperature tape, hand marks and flying dust.

④ Dust in the workplace, water and solvent vapor, smoke, micro particulate organic matter, and the pollution of charged particles attached to PCBA caused by static electricity.

⑤ SMT solder paste printing steel mesh cleaning as daily maintenance, it is essential to clean the residual solder paste on the steel mesh to prevent pollution and ensure the printing quality.